Turbine engines, such as those used on commercial aircraft include many gasflow passages throughout the engine. In order to control the temperature of gas throughout the engine, heat exchangers are used to transfer heat from one gas flow to another gas flow without allowing the gas flows to intermix.
One type of heat exchanger that is often used in turbine engines is a plate/fin heat exchanger. Plate/fin heat exchangers use multiple corrugated sheets to define two sets of passages through which two separate gas flows pass. Heat is transferred through the passage walls joining the two sets of passages without intermixing the gasses between the passages, thereby allowing a hot gas flow in one set of passages to heat a cooler gas flow in the other set of passages or vice versa.
Due to existing corrugated sheet structures, known plate/fin heat exchangers have a rectangular axial cross section. In some applications, such as turbine engine application, the plate/fin heat exchangers are arranged around a central axis. As a result of the rectangular cross section, a radially outward gap occurs between each plate/fin heat exchanger and each adjacent plate/fin heat exchanger when the plate/fin heat exchangers are arranged circumferentially about the axis. The gap creates a dead space that cannot be used and decreases the amount of space available to be used by the heat exchangers.